In an attempt to capture a lion's share of the shoe market, some ambitious shoe makers have made an effort to improve the quality of wearing comfort of the shoes they make. For example, some shoes are provided in the heel portion thereof with a highly elastic pad for enhancing the elasticity of the shoes. However, such shoes have a poor breathing effect. In order to improve the breathing effect of the shoes, some shoe makers have come up with a solution that the insole of a shoe is provided thereon with a breathable shoe pad. Nevertheless, such shoe pad is in fact capable of providing only a very limited breathing effect, because the shoe in itself is not provided with an air-circulating means.